1. Field of the Invention
The present invention relates to an air conditioner in which various setup operations for plural indoor units such as an operation for setting control parameters of the indoor units, a master-slave setup operation for setting the master-slave relationship between the indoor units, etc. can be performed through a controller of an outdoor unit which is connected to the indoor units.
2. Description of the Related Art
In an air conditioner, a control board is generally provided in each control unit of an indoor unit and an outdoor unit. The control board has a CPU (Central Processing Unit), a ROM (Read-only Memory) and other parts mounted thereon, and the CPU accesses various control programs from the ROM to control the driving of various units in the indoor unit and the outdoor unit.
There have recently appeared such an air conditioner that the operation control parameter of an indoor unit can be changed in accordance with a user's request, variation of a use condition or the like. For example, when cooling operation (or heating operation) is interrupted (thermo-off) because the room temperature is coincident with a target temperature, a use may wish to stop air blowing. Further, even when an office and a studio are located in the same building, the dog progress speed of an air filter is different between the office and the studio due to the difference of the amount of floated dust, so that it is preferable that an alarming interval for instructing a filter cleaning work is variable. Normally, the operation control parameters are stored in a non-volatile memory (EEPROM) or the like of the controller of the indoor unit, and the change of these operation control parameters are performed through a remote controller which is provided to each indoor unit.
In the conventional air conditioner as described above, when the operation control parameter is changed, an operator must go to each room in which each indoor unit is mounted and operate the remote control inherent to the indoor unit of the room. However, several tens indoor units are generally mounted in a big office building, a big store or the like, so that a large number of working steps containing movement between rooms are needed to change the operation control parameters of all the indoor units.
Further, with respect to indoor units which are controlled by means of a centralized controller or like (i.e., non-remote-control type indoor units), each indoor unit is provided with no remote controller, and thus the change of the operation control parameter must be performed by preparing a preliminary remote controller and connecting it to each indoor unit.
Still further, the target temperature of a heat exchanger to a set room temperature, the driving rotational number of an air blowing fan to a demanded air quantity, the driving timing of supplementary equipment (humidifier, heater, etc.), etc. are varied between indoor units due to the difference in type (model, capacity), and thus the operation control parameter in conformity with each type is needed individually. In addition, the control board as described above is designed on the assumption that it is commonly used for many types of indoor units. Therefore, various operation control parameters which are respectively matched with various types are collectively stored in the ROM so that a suitable operation control parameter can be selected and used in accordance with a type in which the control board is actually mounted.
The types of indoor units of air conditioners have been recently diversified due to diversified requirements for air condition, and it is now classified into about twenty models such as an in-ceiling type, a floor-mount type, etc. Further, the capacity is set to about ten levels for even indoor units of the same model in accordance with the capacity of a space to be air-conditioned. Accordingly, the number of the types of indoor units is increased to a value in the range from one hundred and several tens to several hundreds. When the same control board is used for each of all the indoor units, the amount of operation control parameters to be stored in ROM of the control board is increased to cover all the types of indoor units and thus it is increased to an extremely large value although only one type of indoor units are actually mounted. Accordingly, a large-capacity ROM must be used, resulting in increase of the manufacturing cost of the overall indoor unit. In view of the foregoing, it has been proposed to setup an exclusively-used control board every type or model of an indoor unit. However, in this case, the types of control boards must be aimlessly diversified, and a production management, an inventory management, etc. become cumbersome. In addition, the manufacturing cost of an indoor unit also rises up because the volume of production is relatively low and there are wide variety of products to be made (i.e., flexible manufacturing system).
Furthermore, a so-called multiroom type air conditioner in which plural indoor units are connected to one outdoor unit has been increasingly required to be set up in a big office building, etc. According to a multiroom air conditioner, each indoor unit may be independently controlled by a remote controller or the like as described above, however, in many cases indoor units which are mounted in the same space to be air-conditioned are grouped and managed under the group control. When indoor units are grouped, it is necessary to set one of the grouped indoor units as a master unit and set the other grouped indoor units as slave units. The master unit of the indoor unit group communicates with a remote controller or an outdoor unit, and further transmits an operation setting (parameters) to the slave units, whereby all the indoor units of the indoor unit group are controlled on the basis of the same operation setting (parameters).
In general, the indoor units are designed in the same construction, and a master/salve change-over switch is provided in the control device of each indoor unit. When a master/slave setting work is performed on the indoor units, a setup operator switches the change-over switch to a master or slave mode every indoor unit to individually set each indoor unit as a master unit or a slave unit.
In the above-described conventional air conditioner, the following problem occurs because the master/slave setting work for each indoor unit group is performed by the setup operator. That is, when the setup operator makes an error to the switching operation, there may occur such a case that plural master units are set for one indoor unit group or all the indoor units are set as slave units. In this case, control signals are mingled between the indoor units and the group control is not performed, so that the setup operation must be quickly corrected. However, when the indoor units are of an in-ceiling type or a built-in duct type, it is very difficult to access to the indoor units after these indoor units are mounted, and thus a large number of steps and a setup time are needed for a re-setup work.